Patent GB-702132-A (GB)
Title: Improvements in or relating to heat exchangers
IPC: H01J19/36
Filed: 1948-06-03
Abstract: 702,132. Tubular heat-exchange elements: cooling systems for electric machines and apparatus. NAAMLOOZE VENNOOTSCHAP PHILIPS' GLOEILAMPENFABRIEKEN. June 3, 1948 [June 6, 19471, No. 14969/48. Class 64(3) [Also in Groups XXVII and XL(a)] At least one side of wall 1, Fig. 1, through which heat exchange takes place between media (the term includes solid bodies as well as fluids), is provided with projecttions, e.g. fins 2 or studs, which define between them a number of continuous or. as shown in Fig. 1, interrupted, channels connected in parallel, there being arranged transversely to said channels a number of supply and discharge passages formed by partitions 4 extending across at least some of the projections so that each supply passage communicates by way of the channels with at least one immediately adjacent discharge passage on either side of the supply passage as indicated by the arrows. Furthermore, the distance e between adjacent channels is not less than 1/50 of the distance a between a supply passage and a discharge passage, being 0.3-6 mm. for continuous channels and 0.3-10 mm. for interrupted channels, and by temperature adjustment log e k is between 0.25 and 4, where k (the cooling factor)= T medium-T wall (input side) T medium-T wall (output side) T being measured in degrees absolute, In Fig. 1, the heat exchange wall 1 is of tubular form with longitudinal fins 2 spaced longitudinally as well as transversely and in a modification of this form, Fig. 2 (not shown), the channels are formed between annular transverse fins and the supply and discharge passages between longitudinal partitions. The fin structures may be arranged inside and/or outside the tube. The heat-exchanger may be used to cool a fluid which is circulated in a closed system to cool apparatus, e.g. an electric machine such as a generator or dynamo or a super-pressure mercuryvapour lamp. In a form which may be used particularly in a vehicle radiator, water flows between headers .40, 42, Fig. 5. up through vertical tubes 41 of elongated cross-section, Fig. 4, provided with vertical longitudinal fins 43. Arranged alternately with the tubes 41 are bent plates 44 which form the transverse supply and discharge passages for cooling air which enters at openings 46 formed by the plates and leaves by similar, rear openings 47 as indicated in broken lines. The plates 44 may be bent so that the longer portions are inclined to the horizontal, Fig. 6 (not shown), not parallel as shown in Fig. 5, and may have side walls with ports therein for the air flow. Specification 514,651, [Group XL], is referred to. The Specification as open to inspection under Sect. 91 comprises also the heatexchanger applied to oil coolers in i.-c. engines, condensers in steam engines, boilers, and heaters and coolers in refrigerators and hot-gas engines (see Group XXVII). Furthermore, a transformer is cooled, Fig. 10 (Cancelled) (not shown), by pumping oil through a heat-exchanger of the present type secured to the transformer and piping the oil to a similar heatexchanger cooled by air from a fan driven by the oil pump motor. This subjectmatter does not appear in the Specification as accepted.